docs(load-graph): classify core libraries and command modules

Third classification batch: the remaining core and library command modules from init.el's early block — external-open, media-utils, auth-config, keyboard-macros, system-utils, text-config, undead-buffers. I annotated each with the load-graph header contract, added a Batch 3 table to the inventory, and extended the validation allowlist. 23 of 102 modules are now classified.

No new hidden dependencies in this batch. auth-config stays eager because other modules need credentials early; the command libraries (external-open, media-utils, keyboard-macros) are eager only by init order and flagged as Phase 4 deferral candidates.

1 files changed, 9 insertions, 0 deletions

diff --git a/modules/media-utils.el b/modules/media-utils.el
index db66a71f3..685530d89 100644
--- a/modules/media-utils.el
+++ b/modules/media-utils.el
@@ -2,6 +2,15 @@
 ;;
 ;;; Commentary:
 ;;
+;; Layer: 3 (Domain Workflow).
+;; Category: D/L.
+;; Load shape: eager.
+;; Eager reason: command library with no side effects; eager only by init order.
+;;   Downloads and players should run by command, so a Phase 4 deferral candidate.
+;; Top-level side effects: none.
+;; Runtime requires: system-lib.
+;; Direct test load: yes (pure command helpers).
+;;
 ;; This library provides reusable Emacs methods for working with online and
 ;; local media, to support media download and playback from Emacs.
 ;;